1.Be trusting yourself. Before you can expect your friends to trust you, you need to show them that you are trustworthy and that you have trust in them. Trust is a risk but when it comes to friendship, you're more likely to make and keep a friend by trusting them than by being a cynic and staying wary all the time.
2.Be kind. Kindness is a large part of developing and maintaining trust because in trusting your friends, you are giving them the gift of compassion and support. It is a great kindness to be able to readily show faith in another person and support them even when they don't feel that same level of faith in themselves. It is kindness that cements the growth of trust.
3.Ask questions. If you ask a lot of questions of a new friend from the very beginning, they will see it as a sign that you are interested in them and their life. This will indicate to them that you're not someone who only thinks about themselves and your friend will begin to confide in you with their deeper feelings and even their innermost secrets.
4.Be humble. Being humble is hard at times but, if you master it, then your friends will not be afraid of you judging them. Being humble is the best approach to reassuring a new friend that you aren't arrogant or condescending. A humble person earns trust because humility is about placing the other person first. In acknowledging that you make mistakes and that you're not all-knowing, your new friends can see that you're an easy person to like and eventually, to trust.
5.Don't tease your new friends. While you may consider it just horseplay or funny, they may see it as demeaning and lacking in respect for them. A person you don't know at the start is a person who will eventually want to confide in you. Teasing or making fun of them is not a good idea because a person who constantly makes fun of people is a person who can't really be trusted and may be insecure enough to be condescending toward the friend out of their earshot.
6.Avoid being demanding. Friendship is about give and take, not about dumping all of your problems on your friend. Trust can be difficult to establish when one friend demands too much time, comfort, support, or reassurance from the other friend.
7.Be non-judgmental. Judging your new friend won't help them to trust you. Initially they may find your "advice" helpful but after a while, when your friends realize that you always think you know what's best for them more than they do, they'll be afraid to come to you with any confidences. Instead, treat your friends fairly, with respect, and with dignity.
8.Talk on the phone. Talking on the phone is an excellent way of getting your friend to open up and share new ideas and thoughts with you. The trick is to ask questions, to use your voice to suggest your emotions, and to try to be serious with them. All of these combined will allow your new friend to reveal things they are feeling at the moment.
9.Share with your friends. Being nice is something easy we can all do. Sharing your things, your time, and your dreams with a new friend is an excellent way for them to grow to trust you. Your new friend will think about the whole of your goodness every now and then. You can share candy, money, clothes, your time, your skills, and even your holiday home.
10.Be Trustworthy. I know from personal experience that its not good to tell al secret or something else that its makes your friend not trust you anymore.
(Collected)